During the Crusades almost a thousand years ago, millions of people were slaughtered predominantly in the name of spreading one religious belief. One could call it an extreme, lethal form of exerting the power of one belief, a sort of power-grabbing proselytizing using weapons such as swords.

Those barbaric Crusades seem like a long time ago and at present most people think that’s a distant past from which we have changed dramatically.

However, today, a new kind of Crusade is underway: the anti-stem cell Crusade. We have a new breed of Crusader (see Nature article here).

Here again some people are proselytizing and in this case their weapons are the Internet and the courts. It is true that these weapons are not like the swords of the old Crusades, but I would argue they are potentially lethal just like the old ones.

So I ask: How many people will die because of the anti-stem cell Crusade?

The goal of the anti-stem cell crowd is to restrict stem cell research only to the type that fits in only with their beliefs. Most often, what this means is that only what they define as moral stem cell research should be allowed. They state as fact that other stem cell research, such as that involving embryonic stem cells, is not only wrong, but also is downright evil. From their perspectives there is no room for differences of opinion.

You might ask, how much harm would really be done if progress on embryonic stem cell research were halted?

The answer is potentially enormous.

There are many conditions for which adult stem cells are quite powerful tools, but 90+% of stem cell scientists will tell you that there are many other conditions that affect millions of people for which adult stem cells will just not work. Yet those conditions might very well be treatable via embryonic stem cells.

As a result, the anti-stem cell Crusade will affect millions of lives negatively. To be clear, these human lives are living, breathing, thinking human beings including 100s of thousands of children.

As we have blogged before here and here, there is a wide diversity amongst different ethnic and religious groups about embryonic stem cell research and when a human life begins. But the stem cell Crusaders will have none of that.

You believe the same as them and act accordingly or you are evil.

The roadblocks put up to the full gamut of stem cell research by the anti-stem Crusaders have already delayed stem cell research potentially by years and discouraged scientists from pursuing this line of research.

For the countless patients waiting for new embryonic stem cell-based treatments for currently non-treatable conditions, the delays caused by the Crusaders may very well mean death.

More generally, what this all means is that we have to view the other side for what they are: Crusaders.

We have to fight back against this non-scientific Crusade because the stakes are high and are measured in human lives. It is vital that we not let these folks control the exchange of information on this topic and rule the Internet with misinformation. Part of this effort means outreach to talk to non-scientists about what stem cells are really all about and why they are important to them personally as well as their loved ones.